Glossary of Pearl Terms E
Edison Pearls: Large beaded freshwater pearls grown in the mollusc gonad in lieu of the mantle. See also Ming Pearls.
EDXRF: Energy dispersive X-ray fluorescence is a spectrometric method of determining chemical composition. It is used to differentiate cultured and natural pearls.
egg shape: Oval shape pearls.
EGL: European Gemological Laboratory.
Ehime Pearl Guild system: Point system developed in 1993 to give farmers exact information about how certain criteria are used to evaluate akoya pearls in Japan.
eightway roller: Perfectly round pearl.
elephant pearl: So-called pearl said to come from the heads or tusk sockets of elephants. See also gajamukta and gajamuthu.
endoscope method: Method of testing whether a pearl is natural or cultured; conducted by inserting a hollow needle into the drill hole of a pearl and examining the behavior of a ray of light projected through the hole and reflected from a small mirror at the end of the needle. The light reflects and bends with the concentric layers of a natural pearl and shines out the drill hole. The light enters the roughly parallel layers of a cultured pearl?s bead and travels through them to the surface.
epithelial cells: Cells on the shell side of a mollusk?s mantle tissue that produce mother of pearl and nacre.
epithelial graft tissue: Piece of mantle tissue from a donor mollusk implanted with a mother-of-pearl bead in the gonad or other body part of a host mollusk to produce a cultured pearl; or implanted with or without a bead in the mantle of a host mollusk to produce a cultured pearl.
essence d?orient: Paste made of several ingredients including scales from the undersides of certain fish. It is applied as a coating to glass beads to make imitation pearls; also called pearly essence.
exotic freshwater pearls: Cultured freshwater pearls that exhibit uncommon colors like green, gold, blue or orange.